In March 2005, The U.S. Commerce Department's Bureau of Industry and Security added the National Standards and Calibration Laboratory (NSCL) to a "list of entities whose activities pose a risk of diverting exported and re-exported items into programs related to weapons of mass destruction." [1] Two years later, the U.S. Department of the Treasury sanctioned the NSCL under Executive Order 13382. [2] However, the U.S. government has not released any more specific information about this organization's activities.

Sources:
[1] "Three Entities Targeted by Treasury for Supporting Syria's WMD Proliferation," U.S. Department of the Treasury, 4 January 2007, www.ustreas.gov.
[2] "U.S. Blacklists Syrian Outfits Over WMD Charges," AFP, 4 January 2007.